A Trust Impact Analysis Model for Composite Service Evolution

Changes to a composite service need to be well analyzed in order to ensure the trust of it. The analysis can be driven by identifying the impact caused by the changes on the trust of other component services as well as the composite service. In this paper, we propose a trust impact analysis model to analyze the impact of two kinds of evolution operations performed on a composite service: binding changes and business process changes. First, trust dependency graph is introduced to analyze the impact on the trust of component services. It not only identifies the affected component services but also quantifies the impact degree on the trust of them. Then we introduce control flow graph to evaluate the impact on the trust of the composite service. Three metrics are introduced to evaluate the impact of these evolution operations. The case study shows how these evolution operations affect the trust of other component services and the composite service which provides a foundation for the evaluation of composite service evolution.